1. Field of the Invention
This invention relates to the field of chemistry. More particularly, this invention relates to laser dyes. Still more particularly, but without limitation thereto, this invention relates to improved laser dyes and laser dye solutions for use with flashlamp and nitrogen laser pumped systems.
2. Description of the Prior Art
In Lee and Robb, Water Soluble Blue-Green Lasing Dyes for Flashlamp-Pumped Dye Lasers, IEEE Journal of Quantum Electronics QE-16, pp 777-784, July 1980, the oxazole dye 2-(4-pyridyl)-5-phenyl oxazole and its pyridinium salts were investigated. This particular salt did lase under normal type flashlamp pumping. Two of these dyes are commercially available from Aldrich Chemical Company, Inc., as dyes 23748-5 and 23749-3.
Benzoxazole and oxidazole derivatives of these pyridinium salts were prepared and did not lase even when pumped with a low power nitrogen laser. Furamoto and Ceccon, Ultraviolet Organic Liquid Lasers, IEEE Journal of Quantum Electronics QE-6, pp 262-268, May 1970, were able to barely lase oxazoles and benzoxazoles under conditions extremely favorable to lasing. They used a fast rise time flashlamp and highly reflective mirrors.
The dyes of the present invention are compounds which are good laser dyes in a spectral region (the 400 nm range) nearly devoid of long lived laser dyes.